FRACTIONS, DECIMALS

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Sale 20 Reductions

• FRACTIONS, DECIMALS PERCENTS
• OH MY!

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The table shows the heights of the ten tallest
buildings in Dallas.
Dallas Tallest Buildings Dallas Tallest Buildings
Building Height (ft)
Bank of America Plaza 921
Renaissance Tower 886
Bank One Center 787
JP Morgan Chase Tower 738
Fountain Place 721
Trammell Crow Center 686
1700 Pacific Avenue 655
Thanksgiving Tower 645
Energy Plaza 629
Elm Place 625

• What fraction of the buildings are between 600
  and 900 feet tall?
• Write this fraction using words.
• Write this fraction as a decimal.

2. Nine-tenths
3. 0.9
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Fractions to Decimals
To change a fraction into a decimal, you divide
the NUMERATOR by the DENOMINATOR. For example,
to change into a decimal, you would divide
the 3 by the 4.
0.
7
5
-2 8 2
0
-2 0 0
This is called a TERMINATING DECIMAL. (it comes
to an end, as in terminate a game!)
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Fractions to Decimals
To change a fraction into a decimal, you divide
the NUMERATOR by the DENOMINATOR. Write each
fraction or mixed number as a decimal.
0.
3
5
Example 1
-6 0 1 0
0
-1 0 0 0
This is called a TERMINATING DECIMAL. (it comes
to an end, as in terminate a game!)
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Fractions to Decimals
To change a fraction into a decimal, you divide
the NUMERATOR by the DENOMINATOR. Write each
fraction or mixed number as a decimal.
We already know that ¾ 0.75
Example 2
Memorizing some conversions like these will make
things a lot EASIER!
¼ 0.25 ½ 0.50
¾ 0.75 (one quarter) (half of
a dollar) (three quarters)
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Fractions to Decimals
To change a fraction into a decimal, you divide
the NUMERATOR by the DENOMINATOR. Write each
fraction or mixed number as a decimal.
0.
3
7
5
Example 3
-2 4 6
0
- 5 6 4
0
- 4 0 0
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Fractions to Decimals
To change a fraction into a decimal, you divide
the NUMERATOR by the DENOMINATOR. Write each
fraction or mixed number as a decimal.
0.
3
3
3..
Example 4
- 9 1
0
- 9 1
0
- 9 1
This is called a REPEATING DECIMAL. (a pattern
in the digits repeats forever!)
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You can use BAR NOTATION to indicate that a
number repeats forever. A bar is written over the
digit(s) that repeat.
Example 5 Write 7/9 as a decimal.
0.
7
7
7
-6 3 7
0
- 6 3 7
0
- 6 3 7
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Decimals to Fractions
To change a decimal into a fraction, you place
the decimal number over the correct pace value
position as a fraction ( /10 /100 /1000)
For example, to change 0.25 into a fraction, you
would place 25 over a denominator of 100 since it
is read twenty-five hundredths. 25/100 1/4
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Copy and complete this chart
Decimal Fraction
1) 0.7
2) 0.08
3) 0.42
4) 0.04
5) 0.71
6) 0.07
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Classwork

• Title Glencoe Pg. 247 21-35
• Advanced Glencoe Pg. 247 27-36, 38-42

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How to change percentages into fractions and
decimals

• A percentage is a special fraction.
• The says, per hundred.
• For example, 47, is simply another way of
  writing the fraction 47/100

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Fractions to Percents

• A ratio is a comparison of 2 quantities by
  division. Fractions are ratios!
• can be written as 34100 in ratio form.
• When a ratio compares a number to 100, it can be
  written as a percent.

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Fractions to Percents

• Ex 1 Annie answered 90 out of 100 questions
  correctly.

Since the fraction already has a denominator of
100, you automatically have the percentage!
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Fractions to Percents

• Ex 2 On average, 50.5 out of 100 students own a
  pet.

Since the fraction already has a denominator of
100, you automatically have the percentage!
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Fractions to Percents
Ex 3 Write as a percent.
Find an equivalent fraction that has a
denominator of 100
x5
x5
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Try These
x5
x5
x20
x20
x4
x4
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You can almost see the 100 in the percentage sign

The zeros
The 1
Percentage Fraction
7 7/100
19 19/100
83 83/100
Etc.
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24 24/100 12/50 6/25
So to write a percentage as a fraction, you
simply put it over 100 like this
24 24/100
Yes, but remember to write the fraction in its
simplest form
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Copy and complete this chart
Percentage Fraction Percentage Fraction
1. 23 23/100 7. 80
2. 24 8. 84
3. 55 9. 12
4. 20 1/5 10. 48
5. 17 11. 71
6. 78 12. 36
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Classwork

• Glencoe Pg. 252 13-29, 34-36
• Advanced Glencoe Pg. 252 10-33 even, 37-40,
  42, 43

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So, to change a percentage into a decimal, you
always divide by 100
Percents to Decimals

• For example, 35 as a fraction is 35/100 so to
  change this into a decimal, you divide 35 by 100
• 35 0.35

100
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To change decimal into a percentage
Decimals to Percents
Decimal
Percentage
To change a decimal into a percentage, you X by
100
X 100
0.23 23
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You Should Know
Decimal to a percentage X 100
A a percentage is a special fraction. 23
23/100
Percentage to a decimal 100
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Copy and complete this chart
Percentage Decimal Decimal Percentage
1. 27 7. 0.87
2. 2 8. 0.08
3. 55 9. 0.42
4. 5 10. 0.04
5. 17 11. 0.71
6. 98 12. 0.07